Police say the suspect threatened the owner of a white Jeep with a knife near Griffith and West around 3 p.m. The woman was able to get her one-year-old child out of the car before the man drove off.
Police spotted the alleged carjacker 40 minutes later and tried to pull him over.
That is when they said he led them on a high-speed chase, ran a stop sign and collided with two other cars at an intersection.
He is now in custody.